Shut-off screw



FIG. 1 is a top perspective view of a shut-off screw showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a left side elevational view thereof;

FIG. 7 is a top plan thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken line showings form no part of the claimed design. 

The ornamental design for a shut-off screw, as shown and described. 